


More Gaster Blaster Underfell

by shadowcat500



Series: The Stuff I write at 1am [4]
Category: Undertale (Video Game)
Genre: Gaster Blaster AU, Underfell, Underswap Papyrus being an asshole, underswap - Freeform
Language: English
Status: In-Progress
Published: 2016-05-26
Updated: 2016-06-11
Packaged: 2018-07-10 10:14:15
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 8
Words: 1,245
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6979171
Author URL: https://archiveofourown.org/users/shadowcat500/pseuds/shadowcat500
Summary: <blockquote class="userstuff">
              <p>Toldja I have more Underfell Gaster Blaster AU!</p>
            </blockquote>





	1. Chapter 1

Red imagined Papyrus coming down the stairs. Finally. That piece of shit would DIE when he finally got his hands on him. Him and his stupid midget of a brother. Red was so consumed in his fantasy of blood (dust? Magic? I'll go with blood XD) that he didn't notice his rapidly changing form. Until he heard the sound of his jacket ripping. Then,   
he noticed the collar round his neck was getting tighter. Suddenly, every ache and unbalance of this growing and malformed form flooded onto him in a tidal wave, nearly causing him to cry out, if years of pain from Boss hadn't made him force it to stay in his throat. Another wave of pain, this time much greater than the first, forced out a deep growl from his throat. A growl? He should of cried out like a normal person! Not a dog! He then realised. That-THING- gaster had made him into once- no, many times- he was turning into it again. But the size of that thing- the basement wouldn't be big enough. He would be crushed!  
Panic forced a whine and a growl from his throat. But he knew that it was too late to hold back the change, and with no Gaster to change him back again- he would be stuck like this. Forever. Shit.  
Yet another wave of agony forced out a whine. The transformation would soon be coming to a 'head'. Heh. As in, it would reach his head and make it into one of his blasters. His eye would be scarlet, and he would keep growing until he reached full size. Which was the size of 3/4 of the testing room. Gaster had told him that he had been at least 300 feet long. This basement was big, at least 10 meters long, but there was no way a giant dragon-skeleton-monster would fit in there. He hoped he would die before the ceiling crushed him.  
Red groaned in pain. He felt his back press slightly against the ceiling. Then, it stopped. Red was confused. Was he dead? He twitched his new tail and stretched his claws. Red growled from the sharp shock of pain. Nope, definitely not dead. But he wasn't growing?   
Gaster must have made it so that he wouldn't be crushed if he transformed in too small of a space. That guy deserved more credit than he got. Red suddenly remembered all that shit Gaster told him when he volunteered for the 'weaponization' project. The stuff about being able to use his natural magic. Good. He would be able to get out of here if he teleported. Oh yeah. He would keep growing. He would need to find somewhere more secluded to be. Thank god for the size of the Snowdin woods.  
Suddenly, he heard someone coming down to the basement.


	2. Chapter 2

Papyrus was worried. Not for Red, of course, that piece of shit deserved it, but for his brother. Whatever was growling and whining in there could be a threat to his brother.  
He tried to open the door. It wouldn't open. He could clearly see a red glow coming from behind it and he heard a menacing growl. Wow, Red really though that some growling and magic could stop Papyrus from stopping him escaping or whatever?! He obviously forgot that Papyrus could teleport.  
Papyrus teleported in there, and Red... What had happened to Red? In his place there was a large skeletal dragon creature, with it's eyes shut. Now that was weird.


	3. Chapter 3

Red could see Papyrus, but he couldn't move to kill him. The change had taken too much out of him, it always did. Wait. It always did? Suddenly, memories of previous timelines had flooded back.

The human had killed everyone, Papyrus, Undyne, Toriel... He knew the universe wouldn't survive this kid, and no one else deserved to die. So he had one last stand in that hall. He'd taken a vial of that 'DT' shit Alphys had, since he'd heard small amounts could increase a monster's magical abilities if they were dying when they took it. It could come in handy.  
He'd put up a good fight, but the human had gotten him eventually, slicing him across the ribs. He knew that now would be a good idea to take the DT, and he did. Things got a little blurry after that, but what he could remember was pain, exhaustion, fear and rage. He remembered the look of sheer terror they looked at him with when the transformation had completed.   
He remembered timelines after that when he had transformed because of Boss, and he'd never been able to change back. Maybe it was because of fear and rage, and it didn't stop until the fear and anger stopped. And the fear NEVER went away if Boss had any say in it.  
Boss had forced him to be a weapon, a pet, so that when the barrier broke he could decimate any human that dared to attack him. 

Papyrus saw the -THING- that Red had turned into and immediately knew that he would have to consult Undyne over this. He could deal with lot of things, but bone dragons from another universe was NOT one of them.


	4. Chapter 4

'What in the name of fuck?!' yelled Papyrus as he saw the large bone dragon in the basement.   
'LANGUAGE!' he faintly heard Blue cry from upstairs.  
The dragon hissed, obviously angry. Papyrus fired up his magic. His brother would NOT be hurt by that thing! He heard gaster blasters fire up behind him. The dragon rolled its eyes in an unmistakably non-feral way. Ok, he could not deal with this. He turned and teleported out.


	5. Chapter 5

Red glared at the door. Soon, that bastard and his midget brother would DIE. When he had the energy, of course. There was nothing he could eat like this, so he would have to rest to regain energy. Red rested his head in his paws and soon fell into the oblivion of sleep .


	6. Chapter 6

**Notes for the Chapter:**

> YES I took inspiration from BOTWOT. Don't judge.

When Red woke up, he was in the Core overflow room. And full size. Thank god the overflow room was twice the size of the testing chamber. But, how did he get here?   
What were they going to do to him?  
And how would he get out?


	7. Chapter 7

Undyne looked nervously at Papyrus. 'S-so you went to your basement and found a smaller version of this guy in there? And when you got here he got this big?'  
'Yup.'  
'And you think removing some of it's magic will make it easier to send it back to it's universe.'  
'Yup.'  
'What if it killed it?'  
'It's better off dead.'  
'O-oh. I guess I'll start the magic removal then.' Undyne flicked the switch.

The first thing Red knew after the ray hit him was that it hurt like fuck. This wasn't just cracked everything pain: This was get torn to pieces pain. He howled in agony. But he knew that this wouldn't fix him. It would only hurt and eventually would only charge his magic, making escape easier. Oh, the irony.  
Oh. God. They were getting desperate and increasing the rate of magic removed. Thank god he was largely determination and not magic. Magic extractors wouldn't do shit.  
But it still hurt like fuck.

'Papyrus it's not doing anything!'  
'What?!' Papyrus was certain that this would work. Red was largely magic, after all. Wait.  
Was it- could it be- DT?


	8. Sorry!

Sorry, but this is discontinued until further notice :(


End file.
